PRODUCTION OF SLIDING MEMBER

摘要

PURPOSE:To produce a sliding member improved in toughness and fatigue strength by casting a sliding member from alloyed cast iron with a specific composition, performing hardening under specific consitions, exerting tempering, and forming the surface of the sliding member into specific structure and specific hardness. CONSTITUTION:A sliding member composed of alloyed cast iron comprising JIS FC20-FC30 equivalent cast iron components or having a composition containing 0.4-0.6wt.% Ni, 0.5-1.0wt.% Cr, and 0.5-1.0wt.% Mo is cast in a metal mold. Subsequently, a sliding part of a temp. between the A1 transformation point and 980 deg.C directly after mold release from the metal mold is subjected to forced cooling to undergo hardening treatment, followed by tempering. By this method, the surface layer part of the sliding part can be formed into a mixed structure of ledeburite structure, obtained by metal mold casting, and tempered martensite structure or tempered sorbite structure, obtained by quench- and-temper treatment, and surface hardness can be regulated to >=HRC55, by which pitting resistance and scuffing resistance can be improved.